AP Psychology Unit 1 (sleep and dreaming)

Circadian Rhythm

The natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours. 

influences patterns of 

• alertness

• hormone release

• body temperature

Jet Lag

A temporary disruption of the body's circadian rhythm due to rapid travel across multiple time zones. It can result in fatigue, sleep disturbances, and difficulty concentrating as the body adjusts to the new time zone.

NREM Stage 1

The first stage of non-rapid eye movement sleep characterized by drifting in and out of sleep, lasting only a few minutes.

• Brain waves slow down, muscles relax, and individuals may experience sudden muscle contractions known as hypnic jerks.

NREM Stage 2

The second stage of non-rapid eye movement sleep characterized by light sleep, lasting about 20 minutes.

• Brain waves further slow down, and sleep spindles (short bursts of brain activity) and K-complexes (sudden, sharp waveforms) appear.

NREM Stage 3

The deepest stage of non-rapid eye movement sleep characterized by the presence of predominantly delta waves.

• Restoration of Resources The process during sleep where the body and brain replenish energy, repair tissues, and remove waste products, promoting physical and mental well-being.

REM (Rapid Eye Movement) Sleep

A stage of sleep characterized by rapid eye movements, vivid dreams, and muscle paralysis.

• It is associated with increased brain activity, including dreaming, and plays a role in memory consolidation and emotional processing.

REM Rebound

The phenomenon where the body increases the time spent in REM sleep after a period of REM deprivation.

• It occurs as a compensatory response to the lack of REM sleep, often resulting in more intense and frequent REM sleep episodes.

Activation-Synthesis (Dreams)

A theory proposing that dreams are the result of random neural activity in the brainstem during REM sleep, which is then interpreted and synthesized by the cerebral cortex into a narrative or story.

Consolidation Theory (Dreams)

A theory suggesting that dreams play a role in the memory consolidation and processing of memories. During sleep, the brain organizes and integrates information acquired throughout the day, contributing to memory storage and learning.

Insomnia

A sleep disorder characterized by difficulty falling asleep, staying asleep, or experiencing restorative sleep, leading to daytime impairment such as fatigue, mood disturbances, and decreased cognitive function.

Narcolepsy

A sleep disorder characterized by excessive daytime sleepiness, sudden episodes of muscle weakness (cataplexy), sleep paralysis, and hallucinations during sleep onset or awakening.

Sleep Apnea

A sleep disorder characterized by pauses in breathing or shallow breathing during sleep, leading to disrupted sleep patterns, daytime fatigue, and other health problems.v

REM Sleep Behavior Disorder

A sleep disorder where individuals physically act out their dreams during REM sleep, potentially causing injury to themselves or others due to loss of muscle paralysis.

Somnambulism

A sleep disorder commonly known as sleepwalking, characterized by walking or performing other activities while still asleep. It typically occurs during non-REM sleep stages and can result in injuries or accidents.